The synthesis of aspirin acetylsalicylic acid from salicylic acid and acetic anhydride is an esterification reaction. The balanced chemical equation for this reaction is:C7H6O3 salicylic acid + C4H6O3 acetic anhydride C9H8O4 aspirin + C2H4O2 acetic acid To achieve the ideal reaction conditions and yield, follow these guidelines:1. Stoichiometry: Use equimolar amounts of salicylic acid and acetic anhydride to ensure that both reagents are consumed completely. For example, if you start with 1 mole of salicylic acid 138.12 g , use 1 mole of acetic anhydride 102.09 g .2. Temperature: The reaction is typically carried out at a temperature of 85-90C. This temperature is high enough to promote the reaction but not too high to cause unwanted side reactions or decomposition of the product.3. Reaction time: Allow the reaction to proceed for about 20-30 minutes at the specified temperature. This time is usually sufficient for the reaction to reach completion.4. Catalyst: Adding a small amount of a strong acid, such as concentrated sulfuric acid H2SO4 , can help catalyze the reaction and increase the yield. Use approximately 1-2 mL of concentrated H2SO4 per mole of salicylic acid.5. Yield: The theoretical yield of aspirin in this reaction is 100%, meaning that if all the salicylic acid reacts with acetic anhydride, you should obtain an equal number of moles of aspirin. However, in practice, the yield is often lower due to side reactions, incomplete reactions, and losses during purification. A typical experimental yield for this reaction ranges from 70-85%.To summarize, for the synthesis of aspirin from salicylic acid and acetic anhydride, use equimolar amounts of the reagents, a temperature of 85-90C, a reaction time of 20-30 minutes, and a small amount of concentrated sulfuric acid as a catalyst. The yield of the reaction is typically between 70-85%.